"We're booked out December 20-23. We have a New Age convention and guests are coming because of the end of the world," said Nebojsa Gajic, manager of the 160-bed, Communist-era Millennium Hotel on the slopes of Mount Rtanj.

The region is selling itself as the best place to survive the looming apocalypse - which will fall on December 21, according to mystics whose calculations depend on the ending of an era in the 5,125-year-old Mayan calendar.

It is basing its promise on the mystical powers that locals say have flooded the area since its pyramid-shaped mountain swallowed a castle belonging to a well-to-do sorcerer, trapping him inside.

About 250 km (155 miles) east of the capital Belgrade, towards Bulgaria, Mount Rtanj is part of the Carpathian range and famed in Serbia for its herbal tea, pristine nature and clean air.

Like the French Pyrenean village of Bugarach - which is guarded by another magical mountain - Rtanj is offering salvation from Friday's cataclysm and safe passage into a golden age.

Residents say they have been inundated with enquiries from Serbia and abroad.

"We're booked out," said Darko Jovic, manager of the Balasevic hotel. "People were even calling from the United States and we had to say 'No'. I couldn't even get a room for my own mother and sister."

The Serbian daily Blic reported the going rate for private accommodation had shot up to 500 euros per night.

A Reuters reporting crew in Rtanj said the area appeared quiet, but bulldozers were clearing the roads of snow in preparation for the expected influx.

"We came because of the end of the world," said Dragoljub Arandjelovic from the nearby town of Paracin. It was unclear if he was serious, or in search of a good party.

"We tried to find a room but without success. If we can't stay here, we'll just have to grin and bear it," he added.

Locals say the sorcerer still lives in the mountain and that there have been sightings of fireballs hovering above Rtanj's foggy peak.

Serbian media reports say physicists have recorded magnetic anomalies in the area, which is riddled with abandoned coal-mine shafts dating from the 19th century.

Retired show-business promoter Dragan Milenkovic, 65, said the mountain, with its striking pyramid shape, was built by aliens who would return on Friday.

"On December 21, on the summit of Rtanj, we'll see a beautiful violet and red light that will engulf the planet for about five seconds and they (the aliens) will come," he told Reuters. "That will mark the beginning of a golden era that will last 1,345 years."

Others were unconvinced.

"For me, doomsday comes every month when I have to cover monthly expenses of 300 euros with a salary of 250 euros and a family of three to feed," said 36-year-old nurse Dragana Djordjevic. (Editing by Matt Robinson and Andrew Heavens)

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